Impact switch

ABSTRACT

A nose impact switch for a projectile comprising a plunger, an insulator, a cover and a O-ring assembled such that when a projectile impacts, the plunger is moved back against a slender rod, constituting a switch function and thereby conducting electrical energy through the plunger to the rod and to a receptor.

Fugelso 1 Feb. 13, 1973 541 IMPACT SWITCH 3,479,476 11/1969 Swain "102 702 R inventor: Mark A. g 521 12th Ave- 3,286,057 11/1966 Krupen ..lO2/70.2 X

SE, Minneapolis, Minn. Primary Examiner-Samuel Feinberg [221 Ffled: June 1970 Assistant Examiner-Thomas H. Webb 2 AWL 44,330 Attorney-R. S. Sciascia and Roy Miller [52 US. Cl. ..102/70.2 R, 200/6153 [57] ABSTRACT [51] Int-Cl --H0lh 35/ F426 5/40 A nose impact switch for a projectile comprising a [58] Field of Search 102/702 R, 70.2 GA; plunger, an insulator, a cover and a O-ring assembled zoo/6195,6153 such that when a projectile impacts, the plunger is moved back against a slender rod, constituting a [56] References Clted switch function and thereby conducting electrical UNITED STATES PATENTS energy through the plunger to the rod and to a recep- 3,169,724 2/1965 Perkins et al. .tlO2/702 R 3,\ 88,953 6/1965 Bianchi et al. ..l02/70.2 R 2 Claims, 1 Drawing Figure PATENTEDFEB13 I975 INVENTOR. MARK A. FUGELSO ROY MILLER ATTORNEY.

IMPACT swrrcn BACKGROUND OF THE INVENTION The nose impact switch is mounted on a forward end of a projectile, such as a 20 mm projectile but is not restricted thereto specifically. The impact switch design is intended to function such that the switch func tion will not take place until an obstacle is encountered. For the retention of the plunger to be perfectly effective, it is absolutely necessary that it should be capable of resisting the static stresses which come into operation under the effect of the inertia of the plunger upon the departure of the projectile from the weapon and also under the action of air pressure. On the other hand,'it is also imperative that the switch function take place upon impact with an obstacle of even very slight resistance.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a cross section of the impact switch assembly.

DESCRIPTION OF THE PREFERRED EMBODIMENT The design comprises a plunger 10, an insulating member 11, a cover 12 and an O-ring l3. Positioned centrally of the insulating member 11 and abutting the O-ring 13 is a penetrator rod 14.

The insulating member 1 1, which is in this instance is formed of Nylon, is coated on the exterior thereof with a copper plating 15.

When the projectile strikes a target, the plunger is physically moved back against the slender rod 14. This action constitutes a switch function. When the switching function occurs, electrical energy is conducted through the plunger 10 to the slender rod 14 and subsequently into an electrical receptor (not shown). In the present instance, the receiver of the electrical energy happens to be a detonator, but it is not necessarily restricted to this receiver.

The O-ring 13 is formed of rubber or some other suitable deformable nonconducting material and physically keeps the plunger 10 from coming in contact with the penetrator rod 14 until impact.

The insulator 11 is made out of Nylon or some other suitable nonconducting material and has screw threads on its outer diameter which allows the complete switch to be mounted on the forward end ofa projectile. Also, the outer surface of the insulator is copper plated so that a complete circuit for the flow of electrical energy, incorporating the outer body of the projectile, may be attained.

The plunger is made out of metal, such as steel or any other suitable material. The cover 12 physically retains the various parts in the proper spaced relationship. The cover is made of aluminum in the present instance, however, could be formed of any other suitable conducting material. Aluminum was selected because of its strength, conductivity and low weight. The cover acts as a conductor between the copper plated outer surface of the insulator 11 and the steel plunger 10.

The primary advantage of the present impact fuze, over the prior art devices, is that the present switch requires about 10 times less force to cause successful operation thereof. Previous switches operated by crushing a metal nose, which requires considerable force to cause successful operation.

What is claimed is:

1. An impact switch assembly adapted for use in a projectile comprising:

an insulating member adaped to be affixed to the forward portion of a projectile;

plunger means forward of said insulating member and fixed in position with respect thereto;

conducting means connecting said plunger means and the projectile;

said conducting means comprising a conductive coating on the exterior of said insulating member;

another conducting means centrally located in said insulating means and spaced from said plunger means such that when said projectile impacts, the plunger means is moved rearwardly with respect to said another conducting means sufficient to contact said another means and form a complete circuit for the flow of electrical energy; and

a deformable insulating O-ring spacer means between said plunger means and said another conductor means.

2. An impact switch assembly as set forth in claim 1 and further including;

a conducting cover means surrounding a portion of said plunger means and extending rearwardly thereof and surrounding an outer portion of said insulating member and in contact with the conductive coating on said insulating member. 

1. An impact switch assemBly adapted for use in a projectile comprising: an insulating member adaped to be affixed to the forward portion of a projectile; plunger means forward of said insulating member and fixed in position with respect thereto; conducting means connecting said plunger means and the projectile; said conducting means comprising a conductive coating on the exterior of said insulating member; another conducting means centrally located in said insulating means and spaced from said plunger means such that when said projectile impacts, the plunger means is moved rearwardly with respect to said another conducting means sufficient to contact said another means and form a complete circuit for the flow of electrical energy; and a deformable insulating O-ring spacer means between said plunger means and said another conductor means.
 1. An impact switch assemBly adapted for use in a projectile comprising: an insulating member adaped to be affixed to the forward portion of a projectile; plunger means forward of said insulating member and fixed in position with respect thereto; conducting means connecting said plunger means and the projectile; said conducting means comprising a conductive coating on the exterior of said insulating member; another conducting means centrally located in said insulating means and spaced from said plunger means such that when said projectile impacts, the plunger means is moved rearwardly with respect to said another conducting means sufficient to contact said another means and form a complete circuit for the flow of electrical energy; and a deformable insulating O-ring spacer means between said plunger means and said another conductor means. 